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11.
B.A. Osei 《Soil Use and Management》1995,11(1):25-29
Abstract. Finely ground calcium carbonate was applied at six rates (0–7.0 t/ha) to samples from four depths of an acid tropical soil (Oxisol). The mixtures were kept moist and maintained at 18 °C for a period of 30 days. There was a significant increase (> 28%) in soil pH at all the sampling depths. Extractable P also increased significantly (> 90%). Significant positive correlations between pH, extractable P and liming rate were obtained ( r > 0.9, P = 0.01). The effect of time was significant only on the 10th day after liming, when soil pH had stabilized. Exchangeable Al was completely eliminated on the 5th day after liming, when most of the soil samples had pH values > 5.0. The results clearly indicate that liming, as a management practice, could be used to alleviate or prevent acidification of Oxisols like the soil studied. 相似文献
12.
Nematode numbers were assessed at 2-week intervals in a coastal savanna soil amended with neem leaves and animal manure for
12 weeks under fallow conditions. The number of plant-parasitic nematodes decreased significantly with the application of
the neem-based amendments, whereas the number of non-parasitic nematodes increased.
http://www.phytoparasitica.org posting July 14, 2005. 相似文献
13.
We identified the perceptions and beliefs that underpin species selection for reforestation among smallholder farmers in the Wassa Amenfi District located in Ghana’s High Forest Zone. Using the Theory of Planned Behaviour as a conceptual framework, we collected perceived outcome beliefs, social referents, and control factors from the farmers with a pre-tested, Likert scaled, structured questionnaire. A Mann–Whitney U test was conducted to test for significance of differences between the responses from farmers already planting trees (PF) and those not planting trees (NPF). We found that NPF were significantly higher than PF in belief strength that tree species that have straight boles, grow fast, and have coppicing abilities are the ideal species for reforestation. We found no significant differences between the farmer groups in their motivation to comply with family members and target market as social referents in species selection; however, NPF were significantly higher in compliance with fellow farmers and landowners. NPF were significantly higher than PF that inadequate planting materials and length of investment are the main control factors, serving as the impediments discouraging NPF from participating in indigenous species reforestation. 相似文献
14.
Reforestation, particularly in the tropics, is of crucial importance for the environment as well as society. However, small planting areas and low participation of smallholder farmers in tree planting programmes often obstruct realisation of set planting area targets. In this regard, we interviewed smallholder farmers undertaking indigenous species reforestation in Oda Kotoamso community within the Wassa Amenfi West District in Western Region of Ghana with a pre-tested questionnaire to identify (1) key socio-economic factors that predict the size of plantations they establish, (2) options that could encourage tree planting among smallholder farmers, and (3) tree species planted by the smallholder farmers and their conservation status according to the IUCN Red List of Threatened Species. Key socio-economic factors were predicted with multiple regression models and ANOVA. Options were ranked on a five-point Likert scale and their differences were tested with the Mann–Whitney U test. Age and income of smallholders are the significant predictors of plantation sizes but farmers’ household size and gender were not significant. Age and income accounted for 77.1% and 22.9%, respectively, of the total variation described by our model (R?2 = 38.4%). In order of importance, incentives (mean = 4.35, SD = 0.48), public nurseries (mean = 4.2, SD = 0.82) and agroforestry (mean = 4.06, SD = 0.56) were the options that could encourage reforestation, though incentives and public nurseries were not significantly different (p > 0.05). Almost half (9 of 19) of the tree species planted are categorised as Vulnerable species, which highlights the contribution of smallholder farmers to recovery of threatened tree species. Our findings suggest that sustainable provision of planting materials in incentivised and youth-based tree planting programmes could increase planting hectarage and conserve threatened tree species. 相似文献
15.
Recent studies have found evidence of a local employment multiplier’s effect. For the most part, these studies provide an average estimate for all labor markets. In this paper, we examine how the average local employment multiplier, the effect of an exogenous increase in employment in the tradable sector on total employment, depends on the characteristics of the local labor market. Specifically, we estimate the average multipliers for coastal, noncoastal, large, and small metropolitan statistical areas (MSAs) across different time periods using the data of 333 US MSAs. Overall, we find a reduced form of local employment multiplier ranging from 1.38 to 2.24, which is within the range of typically estimated local employment multipliers. In addition, the characteristics of the local labor market matter. The local multipliers appear larger in noncoastal and large MSAs. For small and coastal metros, the multiplier is closer to 1.5 than to 2.0 while in the case of large and noncoastal metros, it is closer to 2.0 than to 1.5. The local multipliers are also sensitive to the time period considered. 相似文献
16.
Amoah Isaac Cairncross Carolyn Osei Emmanuel Ofori Yeboah Jacqueline Afua Cobbinah Jesse Charles Rush Elaine 《Plant foods for human nutrition (Dordrecht, Netherlands)》2022,77(3):329-339
Plant Foods for Human Nutrition - Bread is a commonly consumed staple and could be a viable medium to deliver plant-based ingredients that demonstrate health effects. This review brings together... 相似文献
17.
Kossi Lorimpo Adjah Maxwell Darko Asante Aboubacar Toure Mawuli Aziadekey Francis Osei Amoako-Andoh Michael Frei Yacouba Diallo Komi Agboka 《水稻科学》2022,29(6):512-521
Rice plays a paramount role in food and nutrition security in many West African countries. Despite the doubling of production during the last decade, rice consumption has grown faster, creating a deficit between the demand and supply. Although the West African sub-region remains the main rice-producing centre on the continent, production is severely hampered by biotic and abiotic stresses. Drought is one of the factors that most severely reduce grain yields of rice. Systems of production need to be established in order to mitigate yield loss as a result of drought. This review discusses the effects of drought on rice production in West Africa and its mitigation with an emphasis on the improvement of tolerance to drought stress. Yield stability can be achieved by developing drought-tolerant varieties through several processes encompassing profiling of known QTLs and identification of new ones, marker-assisted selection, genomic selection, and extensive multi-locational yield trials. We suggest a comprehensive strategy for breeding drought-tolerant rice varieties in West Africa. 相似文献